Hey Fosse, mate, you're very observant. Here's a wrap of all the Brisbane facilities
The revamped Suncorp Stadium (52,000) is the old Lang Park (28,000) and has traditionaly been used for rugby league and the odd rugby international that Ballymore couldn't fit. The Brisbane Broncos (league team) will be returning to it as their home pitch. Lang Park was always brilliant as no matter where you're seating you were so close to the action.
In Brisbane we also have Ballymore (another rectangular field)which is the cozy home of Rugby and seats 22,000. Super 12 has nearly out grown it and it needs a facelift urgently. I can see all major internationals going to Suncorp now.
ANZ Stadium is around 40,000 seats and was built for the Commonwealth games. it still has the running track. The Broncos moved there a few years ago when their crowds were bigger but being an oval it never suited the game.
The Gabba (about 32000 I think) I'm sure you know is the home of the Queensland cricket side and hosts a test match and 2 ODI's each year. In winter it becomes home to the AFL side the Brisbane Lions. It did host the touring British Lions RU but the wide cricket oval made veiwing tough. Olympic soccer was also played here in 2000.
A side note - Queensland/Brisbane has not been allocated a Bledisloe (aus v nz) cup match for 6 years, even though we provide half of the Wallabies playing staff. From the two yearly games Sydney gets one and the other has been going to Melbourne because they can hold 80,000 bums. Hardly fair when they don't even play the game down there..
All Melbourne Stadiums are oval because of ariel ping pong but they're huge! The MCG can seat 90,000.
NSW has Aussie Stadium - The Olympic Stadium, running track and all but hosts all major football games. League, soccer, union. There is a purpose build league stadium that also hosts the Super 12 called Sydney Football Stadium and seats close to 40,000. All the minor games are played here.
Sydney also have the SCG for cricket and host the Sydney Swans AFL side.
Bit longer winded than I expected.